The removal of unwanted hair from the human epidermis is commonly accomplished by shaving with a razor which, in the male, is a daily exercise for the removal of facial hair and in the female is a regular, but less frequent exercise applied to areas such as the legs and underarms. A wide variety of soaps, creams and oils are available to facilitate the shaving process and lessen the discomfort and trauma to the skin experienced by the razor's actions. Shaving creams are, by far, the preparation of choice for facilitating the act of shaving and lessen the arbrasion, irritation, and localized trauma which, to a greater or lesser extent, is associated with hair removal by shaving. Shaving creams are lather-producing, either through the action of a brush or as propelled from an aerosol container. Both are commonly formulated using soap and/or detergents as the lather forming agent, the latter or brushless shaving cream are oil-in water emulsions of the cream type.
Shaving cream is commonly a lather-forming, soap-based formulation further modified for application with a shaving brush or as a soap-based and/or detergent foam from an aerosol dispenser. Such formulations should provide an easy and rapid production of copious lather; the lather should be resistant to collapse while on the face; there should be a softening of the hair in a viscosity sufficient to hold the hair erect; the lather should provide sufficient lubrication for the razor blade and there should be minimum irritation of the skin. Soaps, particularly those derived from coconut oil, can readily provide a fast lather build-up and experience has shown that those soaps derived from palm oil provide a strong lather. Accordingly, common shaving cream formulations usually contain mixtures of such soaps and/or detergents to meet the requirements of the quality of shaving lather to be produced. Unfortunately, the inclusion of such soaps and/or detergents rendered the shaving cream formulation fairly basic with a pH from about 8 to 10. Since the normal pH of human skin is in the range of pH 4.5, the so-called skin "acid mantle", the application of a shaving preparation of high alkalinity is often irritating to the skin. Although the soap-based and/or detergent shaving cream formulations readily provide a lather of the requisite consistency their natural alkalinity is a significant problem that contributes to the traumatization of the skin during the shaving process.
From the foregoing, it is evident that the requirements of a preferred cream for good lathering properties on the one hand but formulated from non-irritating chemicals presents a problem of considerable dimension to those skilled in the art.
The present invention provides shaving cream formulations that can be readily foamed into a rich shaving lather, are not irritating to the skin, are non-toxic and have the other desired characteristics of shaving stated above.
This invention further provides non-soap and non-detergent containing, non-irritating shaving cream formulations that can be ideally dispensed and applied as an aerosol foam.
This invention also provides a non-soap and non-detergent containing, non-irritating, readily dispensable, shaving cream formulation prepared from safe, non-toxic, economical ingredients.